The Great London [Search results for life] 

The world's attention is now on Proxima Centauri b, a possibly Earth-like planet orbiting the closest star, 4.22 light-years away. The planet's orbit is just right to allow liquid water on its surface, needed for life. But could it in fact be habitable?

If life is possible there, the planet evolved very different than Earth, say researchers at the University of Washington-based Virtual Planetary Laboratory (VPL) where astronomers, geophysicists, climatologists, evolutionary biologists and others team to study how distant planets might host life.

Astronomers at Queen Mary University in London have announced discovery of Proxima Centauri b, a planet orbiting close to a star 4.22 light-years away. The find has been called "the biggest exoplanet discovery since the discovery of exoplanets."

Rory Barnes, UW research assistant professor of astronomy, published a discussion about the discovery at palereddot.org, a website dedicated to the search for life around Proxima Centauri. His essay describes research underway through the UW planetary lab -- part of the NASA Astrobiology Institute -- to answer the question, is life possible on this world?

"The short answer is, it's complicated," Barnes writes. "Our observations are few, and what we do know allows for a dizzying array of possibilities" -- and almost as many questions.

The Virtual Planetary Laboratory is directed by Victoria Meadows, UW professor of astronomy. UW-affiliated researchers include Giada Arney, Edward Schwieterman and Rodrigo Luger. Using computer models, the researchers studied clues from the orbits of the planet, its system, its host star and apparent companion stars Alpha Centauri A and B -- plus what is known of stellar evolution to begin evaluating Proxima b's chances.

Relatively little is known about Proxima:

• It's at least as massive as Earth and may be several times more massive, and its "year" -- the time it takes to orbit its star -- is only 11 days

• Its star is only 12 percent as massive as our sun and much dimmer (so its habitable zone, allowing liquid water on the surface, is much closer in) and the planet is 25 times closer in than Earth is to our sun

• The star may form a third part of the Alpha Centauri binary star system, separated by a distance of 15,000 "astronomical units," which could affect the planet's orbit and history

• The new data hint at the existence of a second planet in the system with an orbital period near 200 days, but this has not been proven

Perhaps the biggest obstacle to life on the planet, Barnes writes, is the brightness of its host star. Proxima Centauri, a red dwarf star, is comparatively dim, but wasn't always so.

"Proxima's brightness evolution has been slow and complicated," Barnes writes. "Stellar evolution models all predict that for the first one billion years Proxima slowly dimmed to its current brightness, which implies that for about the first quarter of a billion years, planet b's surface would have been too hot for Earth-like conditions."

Barnes notes that he and UW graduate student Rodrigo Luger recently showed that had modern Earth been in such a situation, "it would have become a Venus-like world, in a runaway greenhouse state that can destroy all of the planet's primordial water," thus extinguishing any chance for life.

Next come a host of questions about the planet's makeup, location and history, and the team's work toward discerning answers.

• Is the planet "rocky" like Earth? Most orbits simulated by the planetary lab suggest it could be -- and thus can host water in liquid form, a prerequisite for life

• Where did it form, and was there water? Whether it formed in place or farther from its star, where ice is more likely, VPL researchers believe it is "entirely possible" Proxima b could be water-rich, though they are not certain.

• Did it start out as a hydrogen-enveloped Neptune-like planet and then lose its hydrogen to become Earth-like? VPL research shows this is indeed possible, and could be a viable pathway to habitability

• Proxima Centauri flares more often than our sun; might such flares have long-since burned away atmospheric ozone that might protect the surface and any life? This is possible, though a strong magnetic field, as Earth has, could protect the surface.

Also, any life under even a few meters of liquid water would be protected from radiation.

Another concern is that the planet might be tidally locked, meaning one side permanently faces its star, as the moon does Earth. Astronomers long thought this to mean a world could not support life, but now believe planetwide atmospheric winds would transport heat around the planet.

"These questions are central to unlocking Proxima's potential habitability and determining if our nearest galactic neighbor is an inhospitable wasteland, an inhabited planet, or a future home for humanity," Barnes writes.

Planetary laboratory researchers also are developing techniques to determine whether Proxima b's atmosphere is amenable to life.

"Nearly all the components of an atmosphere imprint their presence in a spectrum (of light)," Barnes writes. "So with our knowledge of the possible histories of this planet, we can begin to develop instruments and plan observations that pinpoint the critical differences."

At high enough pressures, he notes, oxygen molecules can momentarily bind to each other to produce an observable feature in the light spectrum.

"Crucially, the pressures required to be detectable are large enough to discriminate between a planet with too much oxygen, and one with just the right amount for life.

As we learn more about the planet and the system, we can build a library of possible spectra from which to quantitatively determine how likely it is that life exists on planet b."

Our own sun is expected to burn out in about 4 billion years, but Proxima Centauri has a much better forecast, perhaps burning for 4 trillion years longer.

"If Proxima b is habitable, then it might be an ideal place to move. Perhaps we have just discovered a future home for humanity. But in order to know for sure, we must make more observations, run many more computer simulations and, hopefully, send probes to perform the first direct reconnaissance of an exoplanet," Barnes writes. "The challenges are huge, but Proxima b offers a bounty of possibilities that fills me with wonder."

Proxima Centauri b may be the first exoplanet to be directly characterized by powerful ground- and space-based telescopes planned for the future, and its atmosphere spectroscopically probed for active biology. The research was funded by the NASA Astrobiology Institute. "Whether habitable or not," Barnes concludes, "Proxima Centauri b offers a new glimpse into how the planets and life fit into our universe."

Author: Peter Kelley | Source: University of Washington [August 30, 2016]

Scientists studying the Chicxulub crater have shown how large asteroid impacts deform rocks in a way that may produce habitats for early life.

Around 65 million years ago a massive asteroid crashed into the Gulf of Mexico causing an impact so huge that the blast and subsequent knock-on effects wiped out around 75 per cent of all life on Earth, including most of the dinosaurs. This is known as the Chicxulub impact.

In April and May 2016, an international team of scientists undertook an offshore expedition and drilled into part of the Chicxulub impact crater. Their mission was to retrieve samples from the rocky inner ridges of the crater -- known as the 'peak ring' -- drilling 506 to 1335 metres below the modern day sea floor to understand more about the ancient cataclysmic event.

Now, the researchers have carried out the first analysis of the core samples. They found that the impact millions of years ago deformed the peak ring rocks in such a way that it made them more porous, and less dense, than any models had previously predicted.

Porous rocks provide niches for simple organisms to take hold, and there would also be nutrients available in the pores, from circulating water that would have been heated inside the Earth's crust. Early Earth was constantly bombarded by asteroids, and the team have inferred that this bombardment must have also created other rocks with similar physical properties. This may partly explain how life took hold on Earth.

The study, which is published today in the >journal Science, also confirmed a model for how peak rings were formed in the Chicxulub crater, and how peak rings may be formed in craters on other planetary bodies.

The team's new work has confirmed that the asteroid, which created the Chicxulub crater, hit the Earth's surface with such a force that it pushed rocks, which at that time were ten kilometres beneath the surface, farther downwards and then outwards. These rocks then moved inwards again towards the impact zone and then up to the surface, before collapsing downwards and outwards again to form the peak ring. In total they moved an approximate total distance of 30 kilometres in a matter of a few minutes.

Professor Joanna Morgan, lead author of the study from the Department of Earth Science and Engineering, said: "It is hard to believe that the same forces that destroyed the dinosaurs may have also played a part, much earlier on in Earth's history, in providing the first refuges for early life on the planet. We are hoping that further analyses of the core samples will provide more insights into how life can exist in these subterranean environments."

The next steps will see the team acquiring a suite of detailed measurements from the recovered core samples to refine their numerical simulations. Ultimately, the team are looking for evidence of modern and ancient life in the peak-ring rocks. They also want to learn more about the first sediments that were deposited on top of the peak ring, which could tell the researchers if they were deposited by a giant tsunami, and provide them with insights into how life recovered, and when life actually returned to this sterilised zone after the impact.

Source: Imperial College London [November 17, 2016]

Extra-terrestrials that resemble humans should have evolved on other, Earth-like planets, making it increasingly paradoxical that we still appear to be alone in the universe, the author of a new study on convergent evolution has claimed.

The argument is one of several that emerge from The Runes Of Evolution, a new book in which the leading evolutionary biologist, Professor Simon Conway Morris, makes the case for a ubiquitous "map of life" that governs the way in which all living things develop.

It builds on the established principle of convergent evolution, a widely-supported theory -- although one still disputed by some biologists -- that different species will independently evolve similar features.

Conway Morris argues that convergence is not just common, but everywhere, and that it has governed every aspect of life's development on Earth. Proteins, eyes, limbs, intelligence, tool-making -- even our capacity to experience orgasms -- are, he argues, inevitable once life emerges.

The book claims that evolution is therefore far from random, but a predictable process that operates according to a fairly rigid set of rules.

If that is the case, then it follows that life similar to that on Earth would also develop in the right conditions on other, equivalent planets. Given the growing number of Earth-like planets of which astronomers are now aware, it is increasingly extraordinary that aliens that look and behave something like us have not been found, he suggests.

"Convergence is one of the best arguments for Darwinian adaptation, but its sheer ubiquity has not been appreciated," Professor Conway Morris, who is a Fellow at St John's College, University of Cambridge, said.

"Often, research into convergence is accompanied by exclamations of surprise, describing it as uncanny, remarkable and astonishing. In fact it is everywhere, and that is a remarkable indication that evolution is far from a random process. And if the outcomes of evolution are at least broadly predictable, then what applies on Earth will apply across the Milky Way, and beyond."

Professor Conway Morris has previously raised the prospect that alien life, if out there, would resemble earthlings -- with limbs, heads, and bodies -- notably at a Royal Society Conference in London in 2010. His new book goes even further, however, adding that any Earth-like planet should also evolve thunniform predators (like sharks), pitcher plants, mangroves, and mushrooms, among many other things.

Limbs, brains and intelligence would, similarly, be "almost guaranteed." The traits of human-like intelligence have evolved in other species -- the octopus and some birds, for example, both exhibit social playfulness -- and this, the book suggests, indicates that intelligence is an inevitable consequence of evolution that would characterise extraterrestrials as well.

Underpinning this is Conway Morris' claim that convergence is demonstrable at every major stepping stone in evolutionary history, from early cells, through to the emergence of tissues, sensory systems, limbs, and the ability to make and use tools.

The theory, in essence, is that different species will evolve similar solutions to problems via different paths. A commonly-cited example is the octopus, which has evolved a camera eye that is closely similar to that of humans, although distinctive in important ways that reflect its own history. Although octopi and humans have a common ancestor, possibly a slug-like creature, this lived 550 million years ago and lacked numerous complex features that the two now share. The camera eye of each must therefore have evolved independently.

Conway Morris argues that this process provides an underlying evolutionary framework that defines all life, and leads to innumerable surprises in the natural world. The book cites examples such as collagen, the protein found in connective tissue, which has emerged independently in both fungi and bacteria; or the fact that fruit flies seem to get drunk in the same manner as humans. So too the capacity for disgust in humans -- a hard-wired instinct helping us avoid infection and disease -- is also exhibited by leaf-cutter ants.

The study also identifies many less obvious evolutionary "analogues," where species have evolved certain properties and characteristics that do not appear to be alike, but are actually very similar. For example, "woodpeckerlike habits" are seen in lemurs and extinct marsupials, while the mechanics of an octopus' tentacles are far closer to those of a human arm than we might expect, and even their suckers can operate rather like hands.

Conway Morris contends that all life navigates across this evolutionary map, the basis of what he describes as a "predictive biology." "Biology travels through history," he writes, "but ends up at much the same destination."

This, however, raises fascinating and problematic questions about the possibility of life occurring on other planets. "The number of Earth-like planets seems to be far greater than was thought possible even a few years ago," Conway Morris said. "That doesn't necessarily mean that they have life, because we don't necessarily understand how life originates. The consensus offered by convergence, however, is that life is going to evolve wherever it can."

"I would argue that in any habitable zone that doesn't boil or freeze, intelligent life is going to emerge, because intelligence is convergent. One can say with reasonable confidence that the likelihood of something analogous to a human evolving is really pretty high. And given the number of potential planets that we now have good reason to think exist, even if the dice only come up the right way every one in 100 throws, that still leads to a very large number of intelligences scattered around, that are likely to be similar to us."

If this is so, as the book suggests in its introduction, then it makes Enrico Fermi's famous paradox -- why, if aliens exist, we have not yet been contacted -- even more perplexing. "The almost-certainty of ET being out there means that something does not add up, and badly," Conway Morris said. "We should not be alone, but we are."

The Runes Of Evolution was six years in the making and draws on thousands of academic sources, and throws up numerous other, surprising findings as well. Sabre-teeth, for example, turn out to be convergent, and Conway Morris explains why it is that the clouded leopard of Asia, Neofelis nebulosa, has developed features that could, as it evolves "presage the emergence of a new sabre-tooth," although sadly it looks set to become extinct before this happens. Elsewhere, the study suggests that certain prehistoric creatures other than bats and birds may have attempted to evolve flight.

"It makes people slightly uneasy that evolution can end up reaching the same solutions to questions about how to catch something, how to digest something, and how to work," Conway Morris added. "But while the number of possibilities in evolution in principle is more than astronomical, the number that actually work is an infinitesimally smaller fraction."

The Runes Of Evolution, by Simon Conway Morris, is published by Templeton Press

Source: University of Cambridge [July 02, 2015]

It took 100 million years for oxygen levels in the oceans and atmosphere to increase to the level that allowed the explosion of animal life on Earth about 600 million years ago, according to a UCL-led study funded by the Natural Environment Research Council.

Before now it was not known how quickly Earth's oceans and atmosphere became oxygenated and if animal life expanded before or after oxygen levels rose. The new study, published today in Nature Communications, shows the increase began significantly earlier than previously thought and occurred in fits and starts spread over a vast period. It is therefore likely that early animal evolution was kick-started by increased amounts of oxygen, rather than a change in animal behaviour leading to oxygenation.

Lead researcher, Dr Philip Pogge von Strandmann (UCL Earth Sciences), said: "We want to find out how the evolution of life links to the evolution of our climate. The question on how strongly life has actively modified Earth's climate, and why the Earth has been habitable for so long is extremely important for understanding both the climate system, and why life is on Earth in the first place."

Researchers from UCL, Birkbeck, Bristol University, University of Washington, University of Leeds, Utah State University and University of Southern Denmark tracked what was happening with oxygen levels globally 770 - 520 million years ago (Ma) using new tracers in rocks across the US, Canada and China.

Samples of rocks that were laid down under the sea at different times were taken from different locations to piece together the global picture of the oxygen levels of Earth's oceans and atmosphere. By measuring selenium isotopes in the rocks, the team revealed that it took 100 million years for the amount of oxygen in the atmosphere to climb from less than 1% to over 10% of today's current level. This was arguably the most significant oxygenation event in Earth history because it ushered in an age of animal life that continues to this day.

Dr Pogge von Strandmann, said: "We took a new approach by using selenium isotope tracers to analyse marine shales which gave us more information about the gradual changes in oxygen levels than is possible using the more conventional techniques used previously. We were surprised to see how long it took Earth to produce oxygen and our findings dispel theories that it was a quick process caused by a change in animal behaviour."

During the period studied, three big 'snowball Earth' glaciations - Sturtian (~716Ma), Marinoan (~635Ma) and Gaskiers (~580Ma) - occurred whereby the Earth's land was covered in ice and most of the oceans were frozen from the poles to the tropics. During these periods, temperatures plummeted and rose again, causing glacial melting and an influx of nutrients into the ocean, which researchers think caused oxygen levels to rise deep in the oceans.

Increased nutrients means more ocean plankton, which will bury organic carbon in seafloor sediments when they die. Burying carbon results in oxygen increasing, dramatically changing conditions on Earth. Until now, oxygenation was thought to have occurred after the relatively small Gaskiers glaciation melted. The findings from this study pushes it much earlier, to the Marinoan glaciation, after which animals began to flourish in the improved conditions, leading to the first big expansion of animal life.

Co-author Prof. David Catling (University of Washington Earth and Space Sciences), added: "Oxygen was like a slow fuse to the explosion of animal life. Around 635 Ma, enough oxygen probably existed to support tiny sponges. Then, after 580 Ma, strange creatures shaped like pizzas lived on a lightly oxygenated seafloor. Fifty million years later, vertebrate ancestors were gliding through oxygen-rich seawater. Tracking how oxygen increased is the first step towards understanding why it took so long. Ultimately, a grasp of geologic controls on oxygen levels can help us understand whether animal-like life might exist or not on Earth-like planets elsewhere."

Source: University College London [December 17, 2015]

Scientists analysing samples from Mars' surface have so far not conclusively detected organic compounds that are indigenous to Mars, which would be indicators of past or present life. The inconclusive results mean that researchers are now suggesting that a good place to find these organic compounds would be deep underground – from rocks that have been blasted to the surface by meteor impacts. This is because such rocks have been sheltered from the Sun's harmful radiation and from chemical processes on the surface that would degrade organic remains.

Now, a team of scientists from Imperial College London and the University of Edinburgh has replicated meteorite blasts in the lab. The aim of the study was to see if organic compounds encased in rock could survive the extreme conditions associated with them being blasted to the surface of Mars by meteorites.  The study, >published in Scientific Reports, suggests that rocks excavated through meteorite impacts may incorrectly suggest a lifeless early Mars, even if indicators of life were originally present.

In the study the team replicated blast impacts of meteorites of around 10 metres in size. The researchers found that the types of organic compounds found in microbial and algal life - long chain hydrocarbon-dominated matter- were destroyed by the pressures of impact. However, the types of organic compounds found in plant matter – dominated by aromatic hydrocarbons - underwent some chemical changes, but remained relatively resistant to impact pressures. Meteorites often contain organic matter not created by life, which have some similarities in their organic chemistry to land plants. The team infer that they also should also be resistant to blast impacts.

Their study could help future missions to Mars determine the best locations and types of blast excavated rocks to examine to find signs of life. For example, it may be that meteorite impacts of a certain size may not destroy organic compounds or scientists may need to concentrate on rocks excavated from a certain depth.

Professor Mark Sephton, co-author of the research from the Department of Earth Science and Engineering at Imperial College London, said: "We've literally only scratched the surface of Mars in our search for life, but so far the results have been inconclusive. Rocks excavated through meteorite impacts provide scientists with another unique opportunity to explore for signs of life, without having to resort to complicated drilling missions. Our study is showing us is that we may need to be nuanced in our approach to the rocks we choose to analyse."

Dr Wren Montgomery, co-author of the study from the Department of Earth Science and Engineering, added: "The study is helping us to see that when organic matter is observed on Mars, no matter where, it must be considered whether the sample could have been affected by the pressures associated with blast impacts. We still need to do more work to understand what factors may play an important role in protecting organic compounds from these blast impacts. However, we think some of the factors may include the depths at which the rock records are buried and the angles at which meteorites hit the Martian surface."

Previous in situ analyses of the Martian terrain have found inconclusive evidence for the existence organic compounds – so far only finding chlorinated organic matter. The issue for scientists has been that it is not easy to look at simple chlorine-containing organic molecules and determine the origin of the organic compound components.

NASA's Viking landers in 1976 detected chlorine-containing organic compounds, but they were thought to be chemical left-overs from cleaning procedures of Viking's equipment before it left Earth. Later, the Phoenix Mission in 2008 discovered chlorine-containing minerals on the Martian surface, but no organic compounds. In 2012 the Mars Science Laboratory Mission detected chlorinated organic matter, but they thought that the analysis process, which involved heating chlorine containing minerals and carbonaceous material together, was producing chlorine-containing organic compounds. Working out whether the source of the carbon found on Mars was carried once again from Earth or was indigenous to Mars remains frustratingly difficult for scientists.

The team carried out their research by subjecting the different types of organic matter to extreme pressure and temperature in a piston cylinder device. They then did a chemical analysis using pyrolysis-gas chromatography mass spectrometry.

The next steps will see the team investigating a broader range of pressures and temperatures, which would help them understand the likely effects of a greater range of meteorite impacts. This would enable them to identify the specific conditions under which organic material may escape the destructive effects of blasts – even when excavated from deep underground by violent events. This could help future Mars missions further refine the types and locations of rocks that they can analyse for signs of past or present life.

Author: Colin Smith | Source: Imperial College London [August 08, 2016]

The National Science Foundation's Green Bank Telescope (GBT) will join in the most powerful, comprehensive, and intensive scientific search ever for signs of intelligent life in the Universe. The international endeavor, known as the Breakthrough Listen, will scan the nearest million stars in our own Galaxy and stars in 100 other galaxies for the telltale radio signature of an advanced civilization.

In a contract signed with the Breakthrough Prize Foundation, significant funding -- approximately $2 million per year for 10 years -- will go to the GBT to participate in this exhilarating journey of discovery.

"Beginning early next year, approximately 20 percent of the annual observing time on the GBT will be dedicated to searching a staggering number of stars and galaxies for signs of intelligent life via radio signals," said Tony Beasley, director of the National Radio Astronomy Observatory, which operates the GBT and other world-class radio astronomy facilities. "We are delighted to play such a vital role in hopefully answering one of the most compelling questions in all of science and philosophy: are we alone in the Universe?"

In addition to the GBT, the Parkes Telescope in Australia will also be involved in this endeavor.

Breakthrough Listen will be the biggest scientific search ever undertaken for signs of intelligent life beyond Earth. It will be 50 times more sensitive and cover 10 times more of the sky than previous searches. In tandem with this radio search, the Automated Planet Finder Telescope at Lick Observatory in California will undertake the world's deepest and broadest search for optical laser transmissions, a tantalizing complementary approach to searching the cosmos for extraterrestrial intelligence.

The $100 million Breakthrough Listen initiative was announced today at the Royal Society in London.

The program will include a survey of the one million closest stars to Earth. It will scan the center of our Galaxy and the entire galactic plane. Beyond the Milky Way, it will search for messages from the 100 closest galaxies. If a civilization based around one of the 1,000 nearest stars transmits to us with the power of common aircraft radar, the GBT and the Parkes Telescope could detect it.

The program will generate vast amounts of data; all of which will be open to the public. This will likely constitute the largest amount of scientific data ever made publicly available. The Breakthrough Listen team will use and develop the most powerful software for sifting and searching this flood of data. All software will be open source. Both the software and the hardware used in the Breakthrough Listen project will be compatible with other telescopes around the world, so that they could join the search for intelligent life. As well as using the Breakthrough Listen software, scientists and members of the public will be able to add to it, developing their own applications to analyze the data.

Breakthrough Listen will also be joining and supporting SETI@home, the University of California, Berkeley ground-breaking distributed computing platform, with 9 million volunteers around the world donating their spare computing power to search astronomical data for signs of life. Collectively, they constitute one of the largest supercomputers in the world.

The 100-meter Green Bank Telescope is the world's largest fully steerable radio telescope. Its location in the National Radio Quiet Zone and the West Virginia Radio Astronomy Zone protects the incredibly sensitive telescope from unwanted radio interference, enabling it to perform unique observations.

Source: National Radio Astronomy Observatory [July 20, 2015]

Hot vents on the seabed could have spontaneously produced the organic molecules necessary for life, according to new research by UCL chemists. The study shows how the surfaces of mineral particles inside hydrothermal vents have similar chemical properties to enzymes, the biological molecules that govern chemical reactions in living organisms. This means that vents are able to create simple carbon-based molecules, such as methanol and formic acid, out of the dissolved CO2 in the water.

The discovery, published in the journal Chemical Communications, explains how some of the key building blocks for organic chemistry were already being formed in nature before life emerged - and may have played a role in the emergence of the first life forms. It also has potential practical applications, showing how products such as plastics and fuels could be synthesised from CO2 rather than oil.

"There is a lot of speculation that hydrothermal vents could be the location where life on Earth began," says Nora de Leeuw, who heads the team. "There is a lot of CO2 dissolved in the water, which could provide the carbon that the chemistry of living organisms is based on, and there is plenty of energy, because the water is hot and turbulent. What our research proves is that these vents also have the chemical properties that encourage these molecules to recombine into molecules usually associated with living organisms."

The team combined laboratory experiments with supercomputer simulations to investigate the conditions under which the mineral particles would catalyse the conversion of CO2 into organic molecules. The experiments replicated the conditions present in deep sea vents, where hot and slightly alkaline water rich in dissolved CO2 passes over the mineral greigite (Fe3S4), located on the inside surfaces of the vents. These experiments hinted at the chemical processes that were underway. The simulations, which were run on UCL's Legion supercomputer and HECToR (the UK national supercomputing service), provided a molecule-by-molecule view of how the CO2 and greigite interacted, helping to make sense of what was being observed in the experiments. The computing power and programming expertise to accurately simulate the behaviour of individual molecules in this way has only become available in the past decade.

"We found that the surfaces and crystal structures inside these vents act as catalysts, encouraging chemical changes in the material that settles on them," says Nathan Hollingsworth, a co-author of the study. "They behave much like enzymes do in living organisms, breaking down the bonds between carbon and oxygen atoms. This lets them combine with water to produce formic acid, acetic acid, methanol and pyruvic acid. Once you have simple carbon-based chemicals such as these, it opens the door to more complex carbon-based chemistry."

Theories about the emergence of life suggest that increasingly complex carbon-based chemistry led to self-replicating molecules - and, eventually, the appearance of the first cellular life forms. This research shows how one of the first steps in this journey may have occurred. It is proof that simple organic molecules can be synthesised in nature without living organisms being present. It also confirms that hydrothermal vents are a plausible location for at least part of this process to have occurred.

The study could also have a practical applications, as it provides a method for creating carbon-based chemicals out of CO2, without the need for extreme heat or pressure. This could, in the long term, replace oil as the raw material for products such as plastics, fertilisers and fuels.

This study shows, albeit on a very small scale, that such products, which are currently produced from non-renewable raw materials, can be produced by more environmentally friendly means. If the process can be scaled up to commercially viable scales, it would not only save oil, but use up CO2 - a greenhouse gas - as a raw material.

Source: University College London [April 27, 2015]

Early Earth was an inhospitable place where the planet was often bombarded by comets and other large astrophysical bodies.

Some of those comets contained complex prebiotic materials, such as amino acids and peptides (chains of amino acids), which are some of the most basic building blocks of life on Earth.

“The survivability of these compounds under impact conditions is mostly unknown,” said Lawrence Livermore’s Nir Goldman, who recently received a NASA grant to continue his astrobiology research. “Our research hopes to answer these questions and give an indication for what types of potentially life-building compounds would be produced under these conditions.”

Basically, Goldman is trying to figure out if life on Earth really did come from out of this world.

Goldman’s early research found that the impact of icy comets crashing into Earth billions of years ago could have produced a variety of small prebiotic or life-building compounds. His work using quantum simulations predicted that the simple molecules found in comets (such as water, ammonia, methanol and carbon dioxide) could have supplied the raw materials, and the impact with early Earth would have yielded an abundant supply of energy to drive the synthesis of compounds like protein forming amino acids. In later work, researchers from Imperial College in London and University of Kent conducted a series of experiments very similar to Goldman’s simulations in which a projectile was fired using a light gas gun into a typical cometary ice mixture. The result: Several different types of amino acids formed.

“Impact events could have not only delivered prebiotic precursors to the primitive planet, but the sudden increase in pressure and temperature from the impact itself was likely a driving factor in synthesizing their assembly into these primary structures,” Goldman said.

Specifically, this new $500,000 grant will fund quantum simulation studies to understand aqueous mixtures of pre-formed amino acids under impact conditions. Goldman’s current efforts will extend his previous work by looking at one step higher in complexity, where extreme pressures and temperatures from impact could induce the formation of more intricate chemical structures like peptide chains or simple proteins.

“Large astrophysical bodies such as comets likely already contain more complex prebiotic materials, like amino acids. It’s possible that pre-existing amino acids would have experienced additional impacts during periods of heavy bombardment on early Earth,” Goldman said. “Our quantum simulations hope to help answer these questions, and to give an indication as to what set of thermodynamic conditions promotes their assembly into larger structures.”

How and when prebiotic organic material appeared on early Earth has been debated for close to 60 years, starting with the seminal Miller-Urey experiments, which showed that amino acids could be produced in aqueous mixtures subjected to electrical discharges, simulating lightning on early Earth.

Large bodies from space are carriers of prebiotic materials. Previous analysis of dust samples from comet Wild 2 has shown the presence of the amino acid glycine in the captured material. In addition, dipeptides (i.e., an amino acid dimer) likely exist in interstellar ices. Assuming survival upon delivery to Earth, these could have acted as catalysts in the formation of a number of prebiotic compounds, including sugars and enzymes.

“Our predictions will help spur future collaboration with experimental groups to characterize the synthesis of primary biomaterials due to exposure to extreme pressures and temperatures,” Goldman said.

Source: Lawrence Livermore National Laboratory [July 07, 2015]

With “Jurassic World” hitting theaters next weekend, it seems like everyone’s got “dino fever” these days. This includes the folks at the National Geographic Channel, who are cashing in on the craze with “T. rex Autopsy,” which features a dissection of the world’s first anatomically correct synthetic Tyrannosaurus Rex. Performing the autopsy are a veterinary surgeon and three leading paleontologists, including University of Edinburgh Chancellor’s Fellow Stephen Brusatte.

“I've been studying T. rex for a decade, but all we really have to go by are bones,” Brusatte told FoxNews.com. “Up until now, my mental image of T. rex has been that of a skeleton, of the bones I study. Now my image is of the incredible model that we built for the program.”

To create the 46–foot long, 880–pound model (the real dinosaurs weighed over 7 tons), England–based special effects house Crawley Creatures consulted some of the world’s leading dinosaur experts, including Brusatte.

“I think the life-sized model that we built for the show is the single most realistic and accurate dinosaur that has ever been assembled,” he said. “It is based on everything we know about T. rex from fossils, with the unknowns filled in by reasonable inference to living crocs (close dinosaur cousins) and birds (living dinosaurs).”

The team used latex rubber, polyurethane foam, silicone rubber, polystyrene, and glass reinforced plastic to create the model, along with 34 gallons of fake blood. They had to get a bit more creative when it came to some of the other details. For example, the feces were made from oatmeal, coffee, and synthetic “badger poo.” In total, it took 1,000 man–hours for the effects house to complete the project.

The four participants weren’t allowed to see the finished product until cameras were rolling at Pinewood Studios in London. Brusatte said that their shocked reactions were completely genuine.

“I consulted on the model-making process, but I never actually saw the physical model as it was being constructed,” he recalled. “There was a fog machine, and the door opened and we walked through the fog to go face–to–face with this life–sized T. rex corpse. I was speechless. The model is beautiful, accurate, and really nails what I think T. rex looked like in the flesh.”

Once over the initial shock, the four had to figure out the synthetic creature’s age, sex and cause of death. For the dissection, they were given a variety of instruments, including a chainsaw. This came in handy when a leg had to be removed to figure out the dino’s age. Fun fact — like a tree, the age of a tyrannosaur can be told from the rings in its bones.

Later, the team had to slice open the belly and through the rib cage to get to the innards inside — a bloody, smelly, and (according to Brusatte) fun process.

“I would have to say my favorite part was when I was literally able to crawl into the belly of the beast and help remove some of the organs, and then poke around to try to figure out whether it was a boy or girl dinosaur. A ‘he rex’ or a ‘she rex,’ ” he said. “Being inside the belly really drove home how enormous T. rex was.”

While performing an autopsy on a life-like synthetic Tyrannosaur makes for entertaining and informative television for the viewers at home, what can the researchers get out of it themselves in terms of their research? Can these kinds of autopsies help scientists gain knowledge about dinosaurs in any way?

“Not really,” Brusatte said, but added that this wasn’t the point of the project.

“I've spent years of my life studying bones — observing, measuring, photographing, [and] describing them,” he explained. “Bones tell you a lot, but there can be a disconnect between bones and a living animal. Taking part in “T. rex Autopsy,” and cutting up the life-sized model, helped me visualize how a real T. rex all fit together– not only the bones, but the muscles, skin, feathers, internal organs.

“The gut was a little bigger than I thought, the teeth even more menacing on a fleshed-out skull, the internal organs much more massive than I imagined before. I will carry this image with me forever,” he added.

“We'll never be able to observe a real T. rex, or ever bring one back through DNA cloning, so I think this model is the closest we're ever going to get,” Brusatte said. “And it's great.”

T. Rex Autopsy premiered on Sunday 7 June, 8pm on National Geographic Channel.

Author: Walt Bonner | Source: FoxNews [June 08, 2015]

Scientists have discovered that the mineral jarosite breaks down organic compounds when it is flash-heated, with implications for Mars research.

Jarosite is an iron sulphate and it is one of several minerals that NASA’s Curiosity Mission is searching for, as its presence could indicate ancient habitable environments, which may have once hosted life on the red planet.

In a new study published today in the journal Astrobiology, researchers from Imperial College London and the Natural History Museum replicated a technique that one of the Curiosity Rover’s on-board instruments is using to analyse soil samples, in its quest to find organic compounds. They tested a combination of jarosite and organic compounds. They discovered that the instrument’s technique -which uses intense bursts of heat called flash-heating – broke down jarosite into sulphur dioxide and oxygen, with the oxygen then destroying the organic compounds, leaving no trace of it behind.

The concern is that if jarosite is present in soil samples that Curiosity analyses, researchers may not be able to detect it because both the jarosite and any organic compounds could be destroyed by the flash-heating process.

In 2014, Professor Mark Sephton, co-author of today’s study, investigated the mineral perchlorate. This mineral also causes problems for flash-heating experiments as it breaks down to give off oxygen and chlorine gas, which in turn react with any organic compounds, breaking them down into carbon dioxide and water. Professor Sephton showed that though perchlorate was problematic, scientists could potentially use the carbon dioxide resulting from the experiment to detect the presence of organic compounds in the sample being analysed.

Professor Sephton, from the Department of Earth Science and Engineering at Imperial College London, said: “The destructive properties of some iron sulphates and perchlorate to organic matter may explain why current and previous missions have so far offered no conclusive evidence of organic matter preserved on Mars’ surface. This is despite the fact that scientists have known from previous studies that organic compounds have been delivered to Mars via comets, meteorites and interplanetary dust throughout its history.”

To make Curiosity’s search for signs of life more effective, the team are now exploring how Curiosity might be able to compensate for the impact of these minerals on the search for organic compounds. Their work could have important implications for both the Curiosity mission and also the upcoming European-led ExoMars 2018 Rover mission, which will be drilling for subsurface samples of the red planet and using the same flash-heating method to look for evidence of past or present alien life.

James Lewis, co-author of the study from the Department of Earth Science and Engineering at Imperial College London, added: “Our study is helping us to see that if jarosite is detected then it is clear that flash-heating experiments looking for organic compounds may not be completely successful. However, the problem is that jarosite is evidence of systems that might have supported life, so it is not a mineral that scientists can completely avoid in their analysis of soils on Mars. We hope our study will help scientists with interpreting Mars data and assist them to sift through the huge amount of excellent data that Curiosity is currently generating to find signs that Mars was once able to sustain life.”

On Earth, iron sulphate minerals like jarosite form in the harsh acidic waters flowing out of sulphur rich rocks. Despite the adverse conditions, these waters are a habitat for bacteria that use these dissolved sulphate ions. This makes these minerals of great interest to scientists studying Mars, as their presence on the red planet provide evidence that acidic liquid water was present at the same time the minerals formed, which could have provided an environment favourable for harbouring ancient microbial Martian life.

On board Curiosity, the Sample Analysis at Mars (SAM) instrument analyses soil samples for evidence of organic compounds by progressively heating samples up to around 1000 C, which releases gases. These gases can then be analysed by techniques called gas chromatography and mass spectrometry, which can identify molecules in the gas and see if any organic compounds are present. It is these SAM instrument experiments that the researchers behind today’s study replicated with jarosite and organic compounds.

The researchers stress that not all sulphates break down to react with organic compounds. For example, those containing calcium and magnesium would not break down until extremely high temperatures were reached during the analysis, and therefore would not affect any organic compounds present.

The team suggest that if jarosite is found in samples on Mars, then it may be possible for Curiosity’s SAM instrument to distinguish a spike in carbon dioxide level, which, as Professor Sephton has shown previously with perchlorate, would act as an indicator that organic material is present and being broken down by the heating process.

The next step will see the researchers using synthetic jarosite in their experiments, which will enable a cleaner decomposition process to occur when the mineral is flash-heated. This will allow for more precise quantitative measurements to be taken when the oxygen is being released. Ultimately, they hope this will enable more precise calculations to be carried out on Mars mineral samples to find ways in which Curiosity can identify the presence of these mineral to mitigate their impact on organic matter.

The jarosite samples used in the experiments in the study were collected from Brownsea Island in Dorset, with the permission and assistance from the National Trust.

Source: Imperial College London [February 19, 2015]

The Museo Civico Archeologico is hosting Egypt. Millennia of Splendour. Beneath the two towers, the splendour of a civilisation that lasted thousands of years and has always fascinated the entire world, has sprung back to life: the Egypt of the pyramids, pharaohs and multiform gods, but also that of sensational discoveries, captivating archaeology, passionate collecting and rigorous scholarship.

The exhibition ‘Egypt’, which is being held at the Museo Civico Archeologico in Bologna, is not just an exposition of high visual and scientific impact, but also an unprecedented international enterprise: the Egyptian collection of the National Museum of Antiquities in Leiden, Netherlands – among the top ten in the world – and that of the Bologna museum – among the most important in Italy for the quantity, quality and state of conservation of its collections – have been brought together in an exhibition space measuring around 1,700 metres, filled with art and history.

500 finds, dating from the Pre-Dynastic Period to the Roman Period, gave been brought from the Netherlands to the Bologna museum. And, together with the masterpieces from Leiden and Bologna, the exhibition also includes important loans from the Museo Egizio in Turin and the Museo Egizio in Florence, creating a network of the most important Italian museums.

For the first time, the masterpieces of the two collections are being displayed side by side, including the Stele of Aku (Twelfth–Thirteenth Dynasty, 1976–1648 BC), the ‘major domo of the divine offering’, with a prayer describing the otherworldly existence of the deceased in a tripartite world divided into sky, earth and the beyond; gold items attributed to General Djehuty, who led the Egyptian troops to victory in the Near East for the great conqueror Pharaoh Thutmose III (1479–1425 BC); the statues of Maya, superintendent of the royal treasury of Tutankhamen, and Merit, a chantress of the god Amun, (Eighteenth Dynasty, reigns of Tutankhamen and Horemheb, 1333–1292 BC), the most important masterpieces in the National Museum of Antiquities in Leiden have left the Netherlands for the first time for the Bologna exhibition; and, among the numerous objects attesting to the refined lifestyle of the most wealthy Egyptians, a Mirror Handle (1292 BC) in the shape of a young woman holding a small bird in her hand.

Lastly, for the first time 200 years after the discovery of his tomb in Saqqara, the exhibition offers the unique and once-in-a-lifetime opportunity to see the important Reliefs of Horemheb reunited: Horemheb was the head commander of the Egyptian army during the reign of Tutankhamen, then rising to become the final sovereign of the Eighteenth Dynasty, from 1319 to 1292 BC and the reliefs are divided between the collections in Leiden, Bologna and Florence.

Thousands of years of the history of a unique civilisation revealed in a major exhibition that brings together masterpieces from important world collections and tells of the pyramids and pharaohs, the great captains and priests, the gods and other divinities, and the people that made Egyptian history and that, thanks to discoveries, archaeology and collecting, never stop enchanting, revealing, intriguing, fascinating and charming generation after generation.

The Seven Exhibition Sections

The Pre-Dynastic and Archaic Periods – At the Origins of History: The transition from raw material to form, from the oral tradition to the written one and from prehistory to history was a fundamental moment for Egyptian civilisation. The Leiden collection is rich in materials documenting the central role played by nature during this long cultural and artistic evolution.

The exhibition opens with a selection of these objects, which are strikingly modern in style, including a vase from the Naqada IID Period (named for a site in Upper Egypt and datable between 3375 and 3325 BC) decorated with ostriches, hills and water motifs. The scene depicted on this vase takes us back to an Egypt characterised by a flourishing landscape later changed over time by climatic changes. Ostriches, here painted red, along with elephants, crocodiles, rhinoceros and other wild animals were common in the Nile region at the time.

The Old Kingdom – A Political/Religious Model Destined for Success and its Weaknesses: The historic period of the Old Kingdom (from the Third to the Sixth Dynasty, roughly between 2700 and 2192 BC) is known for the pyramids and for the consolidation of a bureaucracy at the apex of which stood an absolute sovereign, considered a god on earth and lord of all of Egypt.

This definition of State and its worldly and otherworldly rules, which were highly elitist, are well documented by funerary objects, of which the Leiden museum has a particularly rich collection, including a calcite (alabaster) table for offerings.

Offerings to the deceased were a fundamental part of the funerary ritual, ensuring life after death. The uniqueness of this table, which belonged to a high state official named Defdj, lies in its circular shape, which was unusual, as well as the repetition of the concept of the offering as indicated by the inscription, the sculpted receptacles and, most importantly, the central depiction corresponding to the hieroglyph hotep (offering), or a table upon which one places a loaf of bread.

The Middle Kingdom – The God Osiris and a New Perspective on Life in the Afterworld: The end of the Old Kingdom and the period of political breakdown that followed it led to major changes in Egyptian society, within which the individual had greater responsibility for his own destiny, including in the afterworld. Any Egyptian with the means to build a tomb complete with a sufficient funerary assemblage could now aspire to eternal life. The god Osiris, lord of the afterworld, became Egypt’s most popular divinity.

Many steles now in Leiden and Bologna came from his temple in Abydos, one of Egypt’s most important cult centres. Among them is that of Aku, major domo of the divine offering, who dedicated the stele to Min-Hor-nekht, the form of the ithyphallic god Min worshipped in the city of Abydos. Aku’s prayer to the god describes an otherworldly existence in a tripartite world: the sky, where the deceased were transfigured into stars, the earth, where the tomb was the fundamental point of passage from life to death, and the beyond, where Osiris granted the deceased eternal life.

From the Middle to the New Kingdom – Territorial Control at Home and Abroad: The defeat of the Hyksos, ‘princes from foreign lands’ who invaded and governed northern Egypt for a few generations, marked the beginning of the New Kingdom. An extremely aggressive foreign policy enriched Egypt, and this was one of its periods of greatest splendour. The social class of professional warriors rose to the top of the state hierarchy and spawned a number of ruling dynasties.

The wealth and prestige of these soldiers was also expressed in the production of sophisticated objects, including the gold items attributed to Djehuty, a general under the pharaoh Thutmose III. The Egyptian goldsmith’s art has survived in works of high artistic and economic value, an example being the pectoral element on view in the exhibition.

This piece is a sophisticated exemplar attributed to the tomb of General Djehuty, the man to whom the sovereign Thutmose III entrusted control of his foreign territories. Representing a blue lotus flower, a symbol of rebirth and regeneration, it must have served as the central element of an elaborate pectoral. The scroll engraved on the back suggests that the piece was given personally by Thutmose III.

The Saqqara Necropolis of the New Kingdom: The Leiden and Bologna museums can be considered ‘twins’ in a certain sense, since they house two important groups of antiquities from Saqqara, one of the necropolises of the city of Memphis. During the New Kingdom, this early Egyptian capital returned to its role as a strategic centre for the expansionist policy of the sovereigns of the Eighteenth Dynasty.

This is seen in the funerary monuments of high state officials who held administrative, religious and military roles, including the tombs of the superintendent of Tutankhamen’s royal treasury, Maya, and his wife, Merit, chantress of Amun, and that of Horemheb, head commander of Tutankhamen’s army and the pharaoh’s crown prince.

The statues of Maya and Merit arrived in the Netherlands in 1829 as part of the collection of Giovanni d’Anastasi. More than a century and a half would pass before, in 1986, a British/Dutch archaeological expedition identified the tomb from which they came, southeast of the pyramid of Djoser at Saqqara. These statues, which are the greatest masterpieces in the collection of the National Museum of Antiquities in Leiden, left the Dutch museum for the first time to be displayed in the exhibition.

It should be noted that, when the Egypt Exploration Society of London and the National Museum of Antiquities in Leiden began excavation work southeast of the Djoser pyramid in 1975, the goal was to find the tomb of Maya and Merit. It was therefore a great surprise when they instead discovered the burial of General Horemheb, who had capped off his stunning career by becoming the last sovereign of the Eighteenth Dynasty.

His tomb, which has a temple structure, is characterised by a pylon entrance, three large courts and three cult chapels facing onto the innermost court, which has a peristyle structure. This court is where most of the reliefs preserved in Leiden and Bologna were found, narrating Horemheb’s most important military feats against the populations bordering Egypt: the Asians, Libyans and Nubians.

The New Kingdom – Prosperity after the Conquest: Refined furnishings, musical instruments, table games and jewellery: these are just a few of the luxury goods attesting to the widespread prosperity enjoyed in Egypt as a result of the expansionist policy of the sovereigns of the New Kingdom. Through these sophisticated objects, it is possible to conjure up moments of everyday life, imagining what it was like living inside a royal palace or the residence of a high official. One example in the exhibition is a mirror handle in the graceful, sensual shape of a young women holding a small bird in her hand.

Egypt in the First Millennium: In the first millennium BC, Egypt was characterised by the increasingly clear weakness of its central power to the advantage of local governors who gave themselves the role of ruling dynasts. The loss of political and territorial power weakened Egypt’s defence capacity at its borders, opening the way for Nubian, Assyrian and Persian invasions. The temples remained strong centres of power, and managed a sizeable portion of the economy and the transmission of knowledge, taking on the role of a political intermediary between the ruling power and the devout populace.

Many of the masterpieces on view in the exhibition were part of the funerary assemblages of priests and came from important temple areas. Among them is the sarcophagus of Peftjauneith, which represents the likeness of the god Osiris, wrapped in a linen shroud and with a green face evoking the concept of rebirth. The refined decoration of this sarcophagus confirms the high rank of its owner (the superintendent of the possessions of a temple in Lower Egypt) in the temple sphere. Of particular note is the interior scene of the sky goddess Nut swallowing the sun every evening (to the west) to then give birth to it in the morning (to the east).

Alexander the Great’s conquest of Egypt in 332 BC ended the ‘pharaonic’ phase of Egyptian history. The period of Greek domination was begun by his successors, the Ptolemies, the last of whom was the renowned Cleopatra VII.

The golden decline of Egypt would continue for many more centuries, beyond the Roman conquest in 31 BC up to Arab domination in the sixth century AD.

The dialogue between old and new, local and foreign that distinguished the Greco-Roman period brought a return to high artistic achievements, including the celebrated Fayum portraits, exquisite examples of which from the Leiden collection are on view in the exhibition

Source: Museo Civico Archeologico in Bologna [October 19, 2015]

Astronomers using ESO telescopes and other facilities have found clear evidence of a planet orbiting the closest star to Earth, Proxima Centauri. The long-sought world, designated Proxima b, orbits its cool red parent star every 11 days and has a temperature suitable for liquid water to exist on its surface. This rocky world is a little more massive than the Earth and is the closest exoplanet to us -- and it may also be the closest possible abode for life outside the Solar System. A paper describing this milestone finding will be published in the journal Nature on 25 August 2016.

Just over four light-years from the Solar System lies a red dwarf star that has been named Proxima Centauri as it is the closest star to Earth apart from the Sun. This cool star in the constellation of Centaurus is too faint to be seen with the unaided eye and lies near to the much brighter pair of stars known as Alpha Centauri AB.

During the first half of 2016 Proxima Centauri was regularly observed with the HARPS spectrograph on the ESO 3.6-metre telescope at La Silla in Chile and simultaneously monitored by other telescopes around the world >[1]. This was the Pale Red Dot campaign, in which a team of astronomers led by Guillem Anglada-Escudé, from Queen Mary University of London, was looking for the tiny back and forth wobble of the star that would be caused by the gravitational pull of a possible orbiting planet >[2].

As this was a topic with very wide public interest, the progress of the campaign between mid-January and April 2016 was shared publicly as it happened on the Pale Red Dot website and via social media. The reports were accompanied by numerous outreach articles written by specialists around the world.

Guillem Anglada-Escudé explains the background to this unique search: "The first hints of a possible planet were spotted back in 2013, but the detection was not convincing. Since then we have worked hard to get further observations off the ground with help from ESO and others. The recent Pale Red Dot campaign has been about two years in the planning."

The Pale Red Dot data, when combined with earlier observations made at ESO observatories and elsewhere, revealed the clear signal of a truly exciting result. At times Proxima Centauri is approaching Earth at about 5 kilometres per hour -- normal human walking pace -- and at times receding at the same speed. This regular pattern of changing radial velocities repeats with a period of 11.2 days. Careful analysis of the resulting tiny Doppler shifts showed that they indicated the presence of a planet with a mass at least 1.3 times that of the Earth, orbiting about 7 million kilometres from Proxima Centauri -- only 5% of the Earth-Sun distance >[3].

Guillem Anglada-Escudé comments on the excitement of the last few months: "I kept checking the consistency of the signal every single day during the 60 nights of the Pale Red Dot campaign. The first 10 were promising, the first 20 were consistent with expectations, and at 30 days the result was pretty much definitive, so we started drafting the paper!"

Red dwarfs like Proxima Centauri are active stars and can vary in ways that would mimic the presence of a planet. To exclude this possibility the team also monitored the changing brightness of the star very carefully during the campaign using the ASH2 telescope at the San Pedro de Atacama Celestial Explorations Observatory in Chile and the Las Cumbres Observatory telescope network. Radial velocity data taken when the star was flaring were excluded from the final analysis.

Although Proxima b orbits much closer to its star than Mercury does to the Sun in the Solar System, the star itself is far fainter than the Sun. As a result Proxima b lies well within the habitable zone around the star and has an estimated surface temperature that would allow the presence of liquid water. Despite the temperate orbit of Proxima b, the conditions on the surface may be strongly affected by the ultraviolet and X-ray flares from the star -- far more intense than the Earth experiences from the Sun >[4].

Two separate papers discuss the habitability of Proxima b and its climate. They find that the existence of liquid water on the planet today cannot be ruled out and, in such case, it may be present over the surface of the planet only in the sunniest regions, either in an area in the hemisphere of the planet facing the star (synchronous rotation) or in a tropical belt (3:2 resonance rotation). Proxima b's rotation, the strong radiation from its star and the formation history of the planet makes its climate quite different from that of the Earth, and it is unlikely that Proxima b has seasons.

This discovery will be the beginning of extensive further observations, both with current instruments >[5] and with the next generation of giant telescopes such as the European Extremely Large Telescope (E-ELT). Proxima b will be a prime target for the hunt for evidence of life elsewhere in the Universe. Indeed, the Alpha Centauri system is also the target of humankind's first attempt to travel to another star system, the StarShot project.

Guillem Anglada-Escudé concludes: "Many exoplanets have been found and many more will be found, but searching for the closest potential Earth-analogue and succeeding has been the experience of a lifetime for all of us. Many people's stories and efforts have converged on this discovery. The result is also a tribute to all of them. The search for life on Proxima b comes next..."

>Notes

>[1] Besides data from the recent Pale Red Dot campaign, the paper incorporates contributions from scientists who have been observing Proxima Centauri for many years. These include members of the original UVES/ESO M-dwarf programme (Martin Kürster and Michael Endl), and exoplanet search pioneers such as R. Paul Butler. Public observations from the HARPS/Geneva team obtained over many years were also included.

>[2] The name Pale Red Dot reflects Carl Sagan's famous reference to the Earth as a pale blue dot. As Proxima Centauri is a red dwarf star it will bathe its orbiting planet in a pale red glow.

>[3] The detection reported today has been technically possible for the last 10 years. In fact, signals with smaller amplitudes have been detected previously. However, stars are not smooth balls of gas and Proxima Centauri is an active star. The robust detection of Proxima b has only been possible after reaching a detailed understanding of how the star changes on timescales from minutes to a decade, and monitoring its brightness with photometric telescopes.

>[4] The actual suitability of this kind of planet to support water and Earth-like life is a matter of intense but mostly theoretical debate. Major concerns that count against the presence of life are related to the closeness of the star. For example gravitational forces probably lock the same side of the planet in perpetual daylight, while the other side is in perpetual night. The planet's atmosphere might also slowly be evaporating or have more complex chemistry than Earth's due to stronger ultraviolet and X-ray radiation, especially during the first billion years of the star's life. However, none of the arguments has been proven conclusively and they are unlikely to be settled without direct observational evidence and characterisation of the planet's atmosphere. Similar factors apply to the planets recently found around TRAPPIST-1.

>[5] Some methods to study a planet's atmosphere depend on it passing in front of its star and the starlight passing through the atmosphere on its way to Earth. Currently there is no evidence that Proxima b transits across the disc of its parent star, and the chances of this happening seem small, but further observations to check this possibility are in progress.

This research is >published in the journal Nature.

Source: European Southern Observatory (ESO) [August 25, 2016]

An international research team is formalizing plans to drill nearly 5,000 feet below the seabed to take core samples from the crater of the asteroid that wiped out the dinosaurs.

The group met last week in Merida, Mexico, a city within the nearly 125-mile-wide impact site, to explain the research plans and put out a call for scientists to join the expedition planned for spring 2016. The roughly $10 million in funding for the expedition has been approved and scheduled by the European Consortium for Ocean Research Drilling (ECORD) — part of the International Ocean Discovery Program (IODP) — and the International Continental Scientific Drilling Program (ICDP).

Dinosaurs and other reptiles ruled the planet for 135 million years. That all changed 65.5 million years ago when a 9-mile-wide asteroid slammed into the Earth, triggering a series of apocalyptic events that killed most large animals and plants, and wiped out the dinosaurs and large marine reptiles. The event set the stage for mammals — and eventually humans — to take over. Yet, we have few geologic samples of the now buried impact crater.

Sean Gulick, a researcher at The University of Texas at Austin Institute for Geophysics (UTIG), and a team of scientists from the U.K. and Mexico are working to change that. The team is planning to take the first offshore core samples from near the center of the impact crater, which is called Chicxulub after the seaside village on the Yucatán Peninsula near the crater’s center.

The team, led by Gulick and Joanna Morgan of Imperial College London, will be sampling the crater’s “peak ring” — an enigmatic ring of topographically elevated rocks that surrounds the crater’s center, rises above its floor and has been buried during the past 65.5 million years by sediments.

A peak ring is a feature that is present in all craters caused by large impacts on rocky planetoids. By sampling the Chicxulub peak ring and analyzing its key features, researchers hope to uncover the impact details that set in motion one of the planet’s most profound extinctions, while also shedding light on the mechanisms of large impacts on Earth and on other rocky planets.

“What are the peaks made of? And what can they tell us about the fundamental processes of impacts, which is this dominant planetary resurfacing phenomena?” said Gulick, who is also a research associate professor at the UT Jackson School of Geosciences. UTIG is a research unit of the Jackson School.

The researchers are also interested in examining traces of life that may have lived inside the peak ring’s rocks. Density readings of the rocks indicate that they probably are heavily broken and porous — features that may have served as protected microenvironments for exotic life that could have thrived in the hot, chemically enriched environment of the crater site after impact. Additionally, the earliest recovery of marine life should be recorded within the sediments that filled in the crater in the millions of years after the impact.

“The sediments that filled in the [crater] should have the record for organisms living on the sea floor and in the water that were there for the first recovery after the mass extinction event,” Gulick said. “The hope is we can watch life come back.”

The expedition will last for two months and involve penetrating nearly 5,000 feet beneath the seabed from an offshore platform. The core will be the first complete sample of the rock layers from near the crater’s center.

Once extracted, the core will be shipped to Germany and split in two. Half will be immediately analyzed by an international team of scientists from the U.S., U.K., Mexico and other nations, and half will be saved at a core repository at Texas A&M University for future research needs by the international community.

The team also includes researchers from the National Autonomous University of Mexico (UNAM) and Centro de Investigación Científica de Yucatán (CICY). Scientists interested in joining the mission must apply by May 8, 2015. For more information on the mission and the application process, see the European Consortium for Ocean Research Drilling’s call for applications.

Source: University of Texas at Austin [April 06, 2015]

A new study published by PeerJ documents injuries inflicted in life and death to a large tyrannosaurine dinosaur. The paper shows that the skull of a genus of tyrannosaur called Daspletosaurus suffered numerous injuries during life, at least some of which were likely inflicted by another Daspletosaurus. It was also bitten after death in an apparent event of scavenging by another tyrannosaur. Thus there's evidence of combat between two large carnivores as well as one feeding on another after death.

Daspletosaurus was a large carnivore that lived in Canada and was only a little smaller than its more famous cousin Tyrannosaurus. Like other tyrannosaurs it was most likely both an active predator and scavenger. The individual in question, from Alberta Canada, was not fully grown and would be considered a 'sub-adult' in dinosaur terms (approximately equivalent to an older teenager in human terms). It would have been just under 6 m long and around 500 kg when it died.

Researchers found numerous injuries on the skull that occurred during life. Although not all of them can be attributed to bites, several are close in shape to the teeth of tyrannosaurs. In particular one bite to the back of the head had broken off part of the skull and left a circular tooth-shaped puncture though the bone. The fact that alterations to the bone's surface indicate healing means that these injuries were not fatal and the animal lived for some time after they were inflicted.

Lead author Dr David Hone from Queen Mary, University of London said "This animal clearly had a tough life suffering numerous injuries across the head including some that must have been quite nasty. The most likely candidate to have done this is another member of the same species, suggesting some serious fights between these animals during their lives."

There is no evidence that the animal died at the hands (or mouth) of another tyrannosaur. However, the preservation of the skull and other bones, and damage to the jaw bones show that after the specimen began to decay, a large tyrannosaur (possibly of the same species) bit into the animal and presumably ate at least part of it.

Combat between large carnivorous dinosaurs is already known and there is already evidence for cannibalism in various groups, including tyrannosaurs. This is however an apparently unique record with evidence of both pre- and post-mortem injuries to a single individual.

Source: PeerJ [April 09, 2015]

Photosynthesis is the process by which plants, algae and cyanobacteria use the energy from the Sun to make sugar from water and carbon dioxide, releasing oxygen as a waste product. But a few groups of bacteria carry out a simpler form of photosynthesis that does not produce oxygen, which evolved first.

A new study by an Imperial researcher suggests that this more primitive form of photosynthesis evolved in much more ancient bacteria than scientists had imagined, more than 3.5 billion years ago.

Photosynthesis sustains life on Earth today by releasing oxygen into the atmosphere and providing energy for food chains. The rise of oxygen-producing photosynthesis allowed the evolution of complex life forms like animals and land plants around 2.4 billion years ago.

However, the first type of photosynthesis that evolved did not produce oxygen. It was known to have first evolved around 3.5-3.8 billion years ago, but until now, scientists thought that one of the groups of bacteria alive today that still uses this more primate photosynthesis was the first to evolve the ability.

But the new research reveals that a more ancient bacteria, that probably no longer exists today, was actually the first to evolve the simpler form of photosynthesis, and that this bacteria was an ancestor to most bacteria alive today.

"The picture that is starting to emerge is that during the first half of Earth's history the majority of life forms were probably capable of photosynthesis," said study author Dr Tanai Cardona, from the Department of Life Sciences at Imperial College London.

The more primitive form of photosynthesis is known as anoxygenic photosynthesis, which uses molecules such as hydrogen, hydrogen sulfide, or iron as fuel -- instead of water.

Traditionally, scientists had assumed that one of the groups of bacteria that still use anoxygenic photosynthesis today evolved the ability and then passed it on to other bacteria using horizontal gene transfer -- the process of donating an entire set of genes, in this case those required for photosynthesis, to unrelated organisms.

However, Dr Cardona created an evolutionary tree for the bacteria by analyzing the history of a protein essential for anoxygenic photosynthesis. Through this, he was able to uncover a much more ancient origin for photosynthesis.

Instead of one group of bacteria evolving the ability and transferring it to others, Dr Cardona's analysis reveals that anoxygenic photosynthesis evolved before most of the groups of bacteria alive today branched off and diversified. The results are published in the journal PLOS ONE.

"Pretty much every group of photosynthetic bacteria we know of has been suggested, at some point or another, to be the first innovators of photosynthesis," said Dr Cardona. "But this means that all these groups of bacteria would have to have branched off from each other before anoxygenic photosynthesis evolved, around 3.5 billion years ago.

"My analysis has instead shown that anoxygenic photosynthesis predates the diversification of bacteria into modern groups, so that they all should have been able to do it. In fact, the evolution of oxygneic photosynthesis probably led to the extinction of many groups of bacteria capable of anoxygenic photosynthesis, triggering the diversification of modern groups."

To find the origin of anoxygenic photosynthesis, Dr Cardona traced the evolution of BchF, a protein that is key in the biosynthesis of bacteriochlorophyll a, the main pigment employed in anoxygenic photosynthesis. The special characteristic of this protein is that it is exclusively found in anoxygenic photosynthetic bacteria and without it bacteriochlorophyll a cannot be made.

By comparing sequences of proteins and reconstructing an evolutionary tree for BchF, he discovered that it originated before most described groups of bacteria alive today.

Author: Hayley Dunning | Source: Imperial College London [March 15, 2016]

New research has revealed that fewer than predicted planets may be capable of harboring life because their atmospheres keep them too hot.

When looking for planets that could harbor life, scientists look for planets in the 'habitable zones' around their stars - at the right distance from the stars to allow water to exist in liquid form. Traditionally, this search has focused on looking for planets orbiting stars like our Sun, in a similar way to Earth.

However, recent research has turned to small planets orbiting very close to stars called M dwarfs, or red dwarfs, which are much smaller and dimmer than the Sun. M dwarfs make up around 75 per cent of all the stars in our galaxy, and recent discoveries have suggested that many of them host planets, pushing the number of potentially habitable planets into the billions.

This month, both the TRAPPIST and Kepler planet-hunting telescopes have announced the discovery of multiple near-Earth-sized planets orbiting M dwarf stars, some within the habitable zones.

New research from Imperial College London and the Institute for Advanced Studies in Princeton, published in the >Monthly Notices of the Royal Astronomical Society, has revealed that although they orbit smaller and dimmer stars, many of these planets might still be too hot to be habitable.

The scientists suggest that some of the planets might still be habitable, but only those with a smaller mass than Earth, comparable to Venus or Mars.

Dr James Owen, Hubble Fellow and lead author of the study from the Institute for Advanced Studies in Princeton, said: "It was previously assumed that planets with masses similar to Earth would be habitable simply because they were in the 'habitable zone'. However, when you consider how these planets evolve over billions of years this assumption turns out not to be true."

It was known previously that many of these planets are born with thick atmospheres of hydrogen and helium, making up roughly one percent of the total planetary mass. In comparison, the Earth's atmosphere makes up only a millionth of its mass. The greenhouse effect of such a thick atmosphere would make the surface far too hot for liquid water, rendering the planets initially uninhabitable.

However, it was thought that over time, the strong X-ray and ultraviolet radiation from the parent M dwarf star would evaporate away most of this atmosphere, eventually making the planets potentially habitable.

The new analysis reveals that this is not the case. Instead, detailed computer simulations show that these thick hydrogen and helium envelopes cannot escape the gravity of planets that are similar to or larger in mass than the Earth, meaning that many of them are likely to retain their stifling atmospheres.

However, all is not lost, according to the researchers. While most of the M dwarf planets that are Earth-mass or heavier would retain thick atmospheres, smaller planets, comparable to Venus or Mars, could still lose them to evaporation.

Dr Subhanjoy Mohanty, the other study author from the Department of Physics at Imperial College London, said: "There are hints from recent exoplanet discoveries that relatively puny planets may be even more common around red dwarfs than Earth mass or larger ones, in which case there may indeed be a bonanza of potentially habitable planets whirling around these cool red stars."

Ongoing ground- and space-based searches, and new space missions to be launched in the near future, should provide a definitive answer to this question as well as other questions about the potential suitability of these planets for life.

Author: Hayley Dunning | Source: Imperial College London [May 26, 2016]

Archaeologists from the British museum have reconstructed an ancient man's face, allowing visitors to see what he looked like for the first time.

The man lived 9,500 years ago in the holy city of Jericho, now found in the Palestinian territories near the West Bank.

The 'Jericho skull' was found by British archaeologists in 1953, but until now nobody knew what the he had looked like.

Scientists still don't know the man's true identity, but they speculate that he was once someone of great importance.

This is based on the amount of care people had taken to fill his skull with plaster once he had died, almost 10,000 years ago.

Back then, plastered skulls were a form of ritual burial, like the Egyptians' infamous mummification burials.

The gruesome practice involved removing the corpse's skull and filling it with plaster, before painting over the dead person's face and filling his eye sockets with shells.

These remains were likely put on display for locals while the rest of the body was buried under the family home.

The Jericho skull was found nestled alongside several other plastered skulls, but was by far the most well-preserved of the group.

'He was certainly a mature individual when he died, but we cannot say exactly why his skull, or for that matter the other skulls that were buried alongside him, were chosen to be plastered,' British Museum curator Alexandra Fletcher told >Seeker.

'It may have been something these individuals achieved in life that led to them being remembered after death.'

Before the reconstruction, the ancient skull showed few human features due to the plaster pasting over most of its features.

To investigate the grim burial practice, the scientists sent the skull off for a scan at the Imaging and Analysis Centre at London's Natural History Museum.

Here, a complete micro-CT scan unveiled a ream of new information about the skull, and inspired the Museum to undertake a full plaster reconstruction.

Through the CT scans, the team discovered that the ancient man was missing a jaw underneath the plaster, and had lines of decaying teeth.

They could see he had suffered a broken nose at some point in his life.

He had also undergone head-binding, a traditional practice in which the skull of a human being is deformed intentionally, usually by forcefully distorting a child's skull.

'Head binding is something that many different peoples have undertaken in various forms around the world until very recently,' Fletcher told Seeker.

'In this case, the bindings have made the top and back of the head broader - different from other practices that aim for an elongated shape. I think this was regarded as a 'good look' in Jericho at this time.'

All of the newly gathered details allowed the team to make an accurate plaster reconstruction of the man's head.

And while the fascinating new model provides fresh insight into the man's life, plenty more work needs to be done to discover more about his history and culture.

The team hopes to gather DNA samples from the skull in future, laying out 10,000 year-old genes for investigation.

But the process would be risky - it's likely to damage the skull and useful results aren't guaranteed.

'If we were able to extract DNA from the human remains beneath the plaster, there is currently a very slight chance that we would be able to find out this individual's hair and eye colour,' Fletcher said.

'I say a slight chance because the DNA preservation in such ancient human remains can be too poor to obtain any information.'

The reconstructed face will be on display at the British Museum in London from next Thursday until mid-February.

Author: Harry Pettit | Source: Daily Mail Online [December 09, 2016]

It has long puzzled scientists why, after 3 billion years of nothing more complex than algae, complex animals suddenly started to appear on Earth. Now, a team of researchers has put forward some of the strongest evidence yet to support the hypothesis that high levels of oxygen in the oceans were crucial for the emergence of skeletal animals 550 million years ago.

The new study is the first to distinguish between bodies of water with low and high levels of oxygen. It shows that poorly oxygenated waters did not support the complex life that evolved immediately prior to the Cambrian period, suggesting the presence of oxygen was a key factor in the appearance of these animals.

Lead author Dr Rosalie Tostevin completed the study analyses as part of her PhD with UCL Earth Sciences, and is now in the Department of Earth Sciences at Oxford University. She said: 'The question of why it took so long for complex animal life to appear on Earth has puzzled scientists for a long time. One argument has been that evolution simply doesn't happen very quickly, but another popular hypothesis suggests that a rise in the level of oxygen in the oceans gave simple life-forms the fuel they needed to evolve skeletons, mobility and other typical features of modern animals.

'Although there is geochemical evidence for a rise in oxygen in the oceans around the time of the appearance of more complex animals, it has been really difficult to prove a causal link. By teasing apart waters with high and low levels of oxygen, and demonstrating that early skeletal animals were restricted to well-oxygenated waters, we have provided strong evidence that the availability of oxygen was a key requirement for the development of these animals. However, these well-oxygenated environments may have been in short supply, limiting habitat space in the ocean for the earliest animals.'

The team, which included other geochemists, palaeoecologists and geologists from UCL and the universities of Edinburgh, Leeds and Cambridge, as well as the Geological Survey of Namibia, analysed the chemical elemental composition of rock samples from the ancient seafloor in the Nama Group - a group of extremely well-preserved rocks in Namibia that are abundant with fossils of early Cloudina, Namacalathus and Namapoikia animals.

The researchers found that levels of elements such as cerium and iron detected in the rocks showed that low-oxygen conditions occurred between well-oxygenated surface waters and fully 'anoxic' deep waters. Although abundant in well-oxygenated environments, early skeletal animals did not occupy oxygen-impoverished regions of the shelf, demonstrating that oxygen availability (probably >10 micromolar) was a key requirement for the development of early animal-based ecosystems.

Professor Graham Shields-Zhou (UCL Earth Sciences), one of the co-authors and Dr Tostevin's PhD supervisor, said: 'We honed in on the last 10 million years of the Proterozoic Eon as the interval of Earth's history when today's major animal groups first grew shells and churned up the sediment, and found that oxygen levels were important to the relationship between environmental conditions and the early development of animals.'

The research, based on fieldwork carried out in the Nama Group in Namibia, is published in the >journal Nature Communications.

Source: University College London [September 23, 2016]

The diversity of mammals on Earth exploded straight after the dinosaur extinction event, according to UCL researchers. New analysis of the fossil record shows that placental mammals, the group that today includes nearly 5000 species including humans, became more varied in anatomy during the Paleocene epoch - the 10 million years immediately following the event.

Senior author, Dr Anjali Goswami (UCL Genetics, Evolution & Environment), said: "When dinosaurs went extinct, a lot of competitors and predators of mammals disappeared, meaning that a great deal of the pressure limiting what mammals could do ecologically was removed. They clearly took advantage of that opportunity, as we can see by their rapid increases in body size and ecological diversity. Mammals evolved a greater variety of forms in the first few million years after the dinosaurs went extinct than in the previous 160 million years of mammal evolution under the rule of dinosaurs."

The Natural Environment Research Council-funded research, published today in the Biological Journal of the Linnean Society, studied the early evolution of placental mammals, the group including elephants, sloths, cats, dolphins and humans. The scientists gained a deeper understanding of how the diversity of the mammals that roamed the Earth before and after the dinosaur extinction changed as a result of that event.

Placental mammal fossils from this period have been previously overlooked as they were hard to place in the mammal tree of life because they lack many features that help to classify the living groups of placental mammals. Through recent work by the same team at UCL, this issue was resolved by creating a new tree of life for placental mammals, including these early forms, which was described in a study published in Biological Reviews yesterday.

First author of both papers, Dr Thomas Halliday (UCL Earth Sciences and Genetics, Evolution & Environment), said: "The mass extinction that wiped out the dinosaurs 66 million years ago is traditionally acknowledged as the start of the 'Age of Mammals' because several types of mammal appear for the first time immediately afterwards.

"Many recent studies suggest that little changed in mammal evolution during the Paleocene but these analyses don't include fossils from that time. When we look at the mammals that were present, we find a burst of evolution into new forms, followed by specialisation that finally resulted in the groups of mammals we see today. The earliest placental mammal fossils appear only a few hundred thousand years after the mass extinction, suggesting the event played a key role in diversification of the mammal group to which we belong."

The team studied the bones and teeth of 904 placental fossils to measure the anatomical differences between species. This information was used to build an updated tree of life containing 177 species within Eutheria (the group of mammals including all species more closely related to us than to kangaroos) including 94 from the Paleocene - making it the tree with the largest representation from Paleocene mammals to date. The new tree was analysed in time sections from 140 million years ago to present day, revealing the change in the variety of species.

Three different methods were used by the team to investigate the range and variation of the mammals present and all showed an explosion in mammal diversity after the dinosaur extinction. This is consistent with theories that mammals flourished when dinosaurs were no longer hunting them or competing with them for resources.

Dr Anjali Goswami (UCL Genetics, Evolution & Environment), added: "Extinctions are obviously terrible for the groups that go extinct, non-avian dinosaurs in this case, but they can create great opportunities for the species that survive, such as placental mammals, and the descendants of dinosaurs: birds."

Professor Paul Upchurch (UCL Earth Sciences), co-author of the Biological Reviews study, added: "Several previous methodological studies have shown that it is important to include as many species in an evolutionary tree as possible: this generally improves the accuracy of the tree. By producing such a large data set, we hope that our evolutionary tree for Paleocene mammals is more robust and reliable than any of the previous ones. Moreover, such large trees are very useful for future studies of large-scale evolutionary patterns, such as how early placental mammals dispersed across the continents via land bridges that no longer exist today."

The team are now investigating rates of evolution in these mammals, as well as looking at body size more specifically. Further work will involve building data from DNA into these analyses, to extend these studies to modern mammals.

Source: University College London [December 21, 2015]

In Angkor Wat research, the focus has long been on temples and high society. A new project there is taking a different approach, laying the foundation for a new understanding of the iconic empire

A team excavating a dirt mound at Angkor Wat is hoping to shed light on one of the enduring blank spots in archaeologists’ understanding of the Angkorian empire: the lives of its common people.

It’s a fresh direction in the field of Angkorian archaeology, according to the leader of the dig, Alison Carter, 35, an Honorary Associate at the University of Sydney.

“We’ve spent a lot of time focusing on the temples and inscriptions and the elite members of the society, but there’s still so much that can be learned about the regular people who were contributing to the Angkorian empire. I hope that this project can spark some interest in those regular people,” she said this week.

Carter, an American who has been doing archaeology work in Cambodia for 10 years, said that her excavation was the first of its kind to focus directly on, what she believes to be, an Angkorian-era home.

The project, titled “Excavating Angkor: Household Archaeology at Angkor Wat” which began in early June and will continue through July, is funded primarily by the US-based National Geographic Society, as well as the Dumbarton Oaks institute. It is a part of the larger Greater Angkor Project, an umbrella research initiative managed by the University of Sydney and the APSARA Authority.

“This project is focused on excavating a house mound within the Angkor Wat enclosure. We’re trying to do a horizontal excavation. We’re not opening one huge trench but multiple trenches across this mound, and we’re doing that to try to understand where and how people are living,” Carter said.

“You could [call this] groundbreaking, not just because it is a good archaeological pun, but also because it does signal a shift in how people have been studying Angkor since the French began their research here.”

Carter and her international team are looking for artefacts of daily life – pots, utensils, food remains, gardens – hoping to piece together a picture of what life was like for the non-elite during and after the reign of the Angkor empire from circa 802AD to about 1463AD.

“Basically, anything that anyone does around the house and at home, we’re trying to find material evidence of that,” she added.

The idea for her project stemmed from a 2013 excavation within the Angkor Wat enclosure that found ceramics, cooking vessels, Chinese tradewares and other features that suggested human habitation. It was an important find, said Carter, but one that was largely overshadowed by the published results of another project: an extensive aerial laser surveying – known as lidar – of Angkor and its surrounding temples that was released around the time of the 2013 dig.

Along with evidence of daily activities, Carter and her team are also looking for signs of postholes in their mound.

“It’s a tricky process. It’s hard to study Angkorian houses because the houses themselves were above ground, so we’re using a variety of different strategies to try to pick up as much information as we possibly can,” she said.

Those strategies include methods that have not been used so far in the study of Angkor, such as soil analysis. Through several methods, including analysis of both macro and micro materials, team members can deduce a number of things from the dirt: where there might have been entryways, which areas were used for food preparation and areas where there may have been a garden.

Dougald O’Reilly, a senior lecturer in archaeology at the Australian National University, said that to date, most research of the Khmer empire had examined things mostly from a macro perspective.

“It is encouraging to see this type of work being undertaken to bring to light the subtle nuances of daily life at Angkor at the height of its power. It will bring a far more textured understanding of the past,” O’Reilly said.

Carter said that, due to a binding agreement with National Geographic, she was unable to disclose the specific details of what her team had discovered so far.

However, she did say that the team had discovered a lot of ceramics that seemed to be related to cooking.

“We’re finding evidence of how the mound was constructed and how people might have been living on it,” she said.

Team member Cristina Castillo, from University College London who is studying macrobotanical remains, said they hoped to continue the research in the residential areas to find out more about the local people’s diets and farming systems, which may have included horticultural activities adjacent to their residences.

“After all, rice was the staple, but they were eating a variety of crops, and fish and animals, as well,” she said.

Carter stressed that this excavation was just the beginning of what she hoped would be a renewed focus on the lives of regular Angkorians.

“Once we start getting a bigger data set of house mounds and households then we can really start seeing and saying a lot more about Angkorian society and what the daily lives of people were like,” she said.

“This is the power of archaeological research – to give a voice to these parts of the past.”

Author: Brent Crane | Source: The Phnom Penh Post [July 04, 2015]